1. Field of the Invention
The present invention relates generally to the production of hydrocarbon-containing fluids from subterranean formations. In another aspect, the invention concerns a system for measuring and monitoring the production of a plurality of individual wells, each operating as part of a common production field. In a further aspect, the invention concerns a system for more accurately measuring and continuously monitoring the production of oil, gas, and water from individual hydrocarbon wells, each operating as part of a common production field.
2. Discussion of Prior Art
Conventional systems for measuring and monitoring the production of individual wells in a common production field require an individual to manually perform monthly tests on each well in the field. Each test typically consumes approximately 2 to 8 man-hours and thus, is a labor intensive undertaking, particularly for fields with a high number of individual wells. Further, the results from such manual, monthly individual well tests are suspect due to the limited number of data points collected and the integrity of the testing system if not properly maintained. A typical well testing system may include a test header which is connected in parallel by a plurality of valves with a production header so that production from an individual well can be directed through the test header while the production of the remaining wells is directed through the production header. Such a test header can be costly to install and maintain.
In many areas where hydrocarbons are produced from subterranean formations, in particular the area known as the North Slope of Alaska, periodic manual well tests, as described above, are being used for the custody transfer of unprocessed production between oil fields upstream of the final processing plant. For custody transfer purposes, a minimum of two well tests per month on each well, and additional well tests within 24 hours of any significant operational change of the well is required. Further, a full time surveillance engineer is required to validate the well testing and production allocation process. Using this method for custody transfer requires a significant capital expenditure to standardize all well testing equipment.
Responsive to these and other problems, an object of the present invention is to provide a system for measuring and monitoring individual well production without requiring time-consuming, periodic, manual, individual well tests.
A further object of the present invention is to provide a well production measuring and monitoring system which continuously monitors the production of each individual well.
A still further object of the present invention is to provide an individual well production measuring and monitoring system which allows for the elimination of costly test headers.
An even further object of the present invention is to provide a system for more accurately measuring the production of a plurality of individual wells operating as part of a common production field.
It should be noted that the above-listed objects need not all be accomplished by the invention claimed herein, and other objects and advantages of this invention will be apparent from the following description of the invention and appended claims.
In accordance with one embodiment of the present invention, a method of determining fluid production from a plurality of individual hydrocarbon wells is provided. The method comprises the steps of: (a) simultaneously measuring a plurality of individual well multi-phase flow measurements, each indicative of the fluid produced by a respective one of the individual wells; (b) measuring a combined multi-phase flow measurement of the combined fluid cooperatively produced by all of the individual wells; and (c) allocating the combined multi-phase flow measurement from step (b) to each of the individual wells based on the individual well multi-phase flow measurements from step (a) to thereby determine an adjusted individual well multi-phase flow measurement for each individual well, the adjusted individual well multi-phase flow measurements providing a more reliable indication of actual multi-phase fluid production from each individual well than the individual well multi-phase flow measurements from step (a).
In accordance with another embodiment of the present invention, a method of determining fluid production from a plurality of individual hydrocarbon wells is provided. The method comprises the steps of: (a) simultaneously measuring an upstream multi-phase flow of the fluid produced by each individual well; (b) generating a plurality of upstream flow signals each indicative of the upstream multi-phase flow of a respective individual well; (c) measuring a downstream multi-phase flow of the combined fluid cooperatively produced by all of the individual wells; (d) generating a downstream flow signal indicative of the downstream multi-phase flow of all the individual wells; and (e) computing an adjusted upstream multi-phase flow measurement based on the upstream and downstream flow signals by allocating the downstream multi-phase flow to each individual well based on the upstream multi-phase flow, the adjusted multi-phase flow measurement provides a more accurate indication of the actual multi-phase flow of the fluid produced by each individual well than the upstream multi-phase flow measured in step (a).
In accordance with a further embodiment of the present invention, a method of determining fluid production from a plurality of individual hydrocarbon wells is provided. The method comprises the steps of: (a) simultaneously measuring a plurality of upstream gas flow rates, each indicative of the flow rate of an upstream gas-phase component of the fluid produced by an individual well; (b) simultaneously measuring a plurality of upstream liquid flow rates each indicative of the flow rate of an upstream liquid-phase component of the fluid produced by an individual well; (c) measuring a plurality of upstream water-cuts each indicative of the amount of water in the upstream liquid-phase component of the fluid produced by an individual well; (d) physically combining the fluids produced by all of the individual wells into a combined flow; (e) physically separating the combined flow into a downstream gas-phase cut and a downstream liquid-phase cut; (f) measuring a downstream gas flow rate indicative of the flow rate of the downstream gas-phase cut; (g) measuring a downstream liquid flow rate indicative of the flow rate of the downstream liquid-phase cut; and (h) physically recombining the downstream gas-phase cut and the downstream liquid-phase cut.
In accordance with a still further embodiment of the present invention, an apparatus for measuring fluid production from a plurality of individual wells is provided. The apparatus generally comprises a plurality of upstream metering devices and a downstream metering device. Each of the upstream metering devices are adapted to be fluidically coupled to a respective individual well. Each of the upstream metering devices is operable to measure an upstream gas flow rate and an upstream liquid flow rate of the fluid produced by a respective individual well. The downstream metering device is adapted to be fluidically coupled to all of the individual wells and is operable to measure a downstream gas flow rate and a downstream liquid flow rate of the combined fluid cooperatively produced by all the individual wells.
In accordance with still another embodiment of the present invention, an apparatus for measuring fluid production from a plurality of individual hydrocarbon wells is provided. The apparatus generally comprises a plurality of upstream metering devices, a downstream metering device, and a computing device. Each of the upstream metering devices is adapted to be fluidically coupled to a respective individual well. Each of the upstream metering devices is operable to measure an upstream multi-phase flow of the fluid produced by a respective individual well. Each of the upstream metering devices is operable to generate an upstream flow signal indicative of the upstream multi-phase flow of the respective individual well. The downstream metering device is adapted to be fluidically coupled to all of the individual wells. The downstream metering device is operable to measure a downstream multi-phase flow of the combined fluid produced by all of the individual wells. The downstream metering device is operable to generate a downstream flow signal indicative of the downstream multi-phase flow of the combined fluid produced by all the individual wells. The computing device is operable to receive the upstream and downstream flow signals and compute a plurality of adjusted multi-phase individual well flow measurements by allocating the downstream multi-phase flow to each individual well based on the upstream multi-phase flow for each individual well.